1. Field of the Invention
The present invention relates to a brushless motor. More specifically, the present invention relates to an axially gapped type brushless motor used as a driving source, for example, of a rotary head of a video tape recorder and a disk player and so on.
2. Description of the Prior Art
An example of the interesting prior art brushless motor of the present invention is disclosed, for example, in U.S. Pat. No. 4,093,897 issued on June 6, 1978 or in Japanese Patent Application Laying Open No. 57687/1981 laid open on May 18, 1981. The brushless motor of the prior art as disclosed therein includes a stator and a rotor, and stator coils or driving coils are mounted on an upper surface of a stator yoke plate included in the stator and a printed circuit board is disposed on the driving coils. On the printed circuit board, there is provided a rotor magnet which is fixed to a rotor having a shaft. A rotation torque is generated on the rotor, that is on the rotary shaft by the interlinkage between the magnetic field system produced by the driving coils and the magnetic flux from the rotor magnet.
In such brushless motor of the prior art, since the printed circuit board is interposing between the driving coils and the rotor magnet, a gap therebetween is large and consequently a motor efficiency is poor. If the motor efficiency is poor, for example, a large electric current is required for the driving coils, which leads, therefore, not only to a high consumption of electric power, but also to various problems such as the requirement of circuit components endurable to such large electric current.